On the Energy Absorption and Acceleration Mitigation of 3D Printed Lattice Structures with Computed Tomography (CT) Scan Damage Analysis

Recent advances in additive manufacturing have allowed the investigation of the static and dynamic performance of 3-dimensional cellular structures for the application of absorbing mechanical energy. This manuscript examines the performance of body-centered cubic (BCC), face-centered cubic (FCC), diamond cubic (DC), and Kelvin truss (KT) lattice structures. Using a commercially available Ultraviolet Ray (UV)-cured additive manufacturing process, these structures are made of Digital ABS and Shore hardness 60 (SH60) digital materials. The lattice structures were investigated at multiple strain rates under static compression and low velocity impact. The area under the stress–strain response, i.e. total strain energy, is considered as a measure for energy absorption under static test. For low velocity impacts, the differences in acceleration from the top impacted surface and the base of the lattice structure are recorded and are used as a measure for dynamic energy absorption in the context of impact resistance and protection. In static compression it was observed that the FCC and KT lattices had nearly two times more energy absorption compared to the BCC and DC lattices. Under impact the BCC reduced the most acceleration followed by the DC, FCC, and KT lattice. High-speed footage captures fracture modes during impact, while micro-CT scanning visualizes fracture surfaces and predicts damage and failure mechanisms. These findings offer insights into how into how strain rate and inertia variations influence energy absorption, acceleration mitigation, and failure modes of lattice structures, contributing to the development of future novel designs.